Over 330 km of traffic jams as France swelters in summer heat

French motorists faced 332 kilometres of traffic jams midday Saturday as local and foreign holidaymakers headed south to Riviera beaches or onto Italy and Spain. As most of the country sweltered in temperatures over 30°C , storm warnings were issued for Brittany and the western Loire valley.

Some of the worst traffic was in the Paris region - 35 kilometres of traffic jams in the Ile de France region and snail-pace speeds on the Paris capital's ringroad and on the A6 and A10 motorways, according to the Bison Futé traffic-watcher.

There was more trouble further down the A6, the main motorway heading for the Mediterranean, with 65 kilometres of tailbacks between Tournus, in Burgundy, and Orange, in Provence.

Motorists heading for Italy had to wait an hour to enter the Mont Blanc tunnel, while there were five-kilometre hold-ups at Nimes and six-hour hold-ups at Montpellier on the route for Spain.

France's chilly, wet spring has given way to temperatures of 30°C and forecasts that they will continue to rise in the coming week, hitting 35°C even in the north of the country.

Interactive map of France

Since the 2003 heatwave, in which 15,000 people are believed to have died prematurely, France has had an emergency plan that comes into action if the thermometer fails to go below 20°C.

Weather forecasters issued severe storm warnings for the west of the country on Saturday.

Brittany and four départements in the Loire were likely to be hit by serious storms any time after 3.00pm, Météo France said and it advised residents not to use the telephone or other electrical devices as the storms brewed.

Hail was forecast in Burgundy and less severe storms in parts of the Pyrenees, the Alps and Auvergne.